There is also predictionbook, which seems to be a similar sort of thing.
Of course, there's also metaculus, but that's more of a collaborative prediction aggregator, not so much a personal tool for tracking your own predictions.
Hey all, I have been working on a way to keep track of testable statements, do you know of any such tools?
The one I have focused on is this one: https://questpowered.com , but I would be curious to know of other ones.